Ger/Converts- Is a convert obligated to honor and fear his parents?
Hitting or cursing or shaming: One who converted is not liable [for hitting or cursing] his father or mother. This applies even if his father or mother also converted. Even if a woman converted when she was already pregnant, then the child born is not liable [for hitting or cursing] his father or mother. [Nevertheless,] it remains forbidden for a convert to curse or hit or shame his father [or mother] in order so people do not say that his conversion caused him to leave a higher state of holiness to a lower state of holiness. This applies even if his parents are idol worshipers.
Honoring and fearing: Due to the reason stated above, a Ger is Rabbinically obligated to slightly respect his Gentile parents. [This especially applies if the parents also converted and are now Jewish. Nevertheless, even then the obligation of respect is only Rabbinical even if the mother converted while pregnant. He is to respect his parents on the same level that is accepted within the Gentile world. However, some Poskim rule that he is to honor his parents to the same level that a child must honor Jewish parents. If one’s Gentile parents are ill one is to care for them if there is no one else available to do so.]
Ger/convert mourning his gentile parent: A convert does not mourn the passing of his relatives. This applies even if his relatives converted as well. Thus, a convert does not mourn the passing of his children who converted. Likewise, a convert does not mourn the passing of a parent who converted. [Likewise, a convert who had a Jewish father does not mourn his passing. If, however, the mother converted while pregnant with the child, then the mother and child mourn each other’s passing, although the child and father do not mourn each other’s passing even if he converted with them. Practically, the child may choose to mourn a non-Jewish parent if not doing so will cause embarrassment to the family.]
Ger/convert saying Kaddish for his gentile parent? Yes. However, he is to try to do so inconspicuously.
Ger/convert praying for his gentile parent: A convert’s prayer on behalf of his parents does not help [to the same extent as a regular son who Davens for his father]. [However, he may Daven for him if he so chooses, and such a prayer does have some affect.]
From the Rav’s Desk
Dear Rabbi, I am a convert, but my father was Jewish and would like to know whether I should keep the Yahrzeit of my father as well as whether I receive precedence to lead the prayer for the Amud over somebody who is within the year of mourning. Basically, we only have a single minyan available and the person who is within his year of mourning for his mother generally leads the prayers, although he gives it up for anyone who has a Yahrzeit, and I would like to know if I receive the same status?
Being that you are a righteous convert, therefore from the letter of the law you are not obligated to keep the Yahrzeit customs for your biological Jewish father. Nonetheless, you may do so if you choose and so is recommended. Thus, you should keep the regular Yahrzeit customs. However, you cannot differ somebody else from his rights to the Amud during his year of mourning for his parent, although if the person agrees he may forgo that right on your behalf, if he chooses.
Explanation: A convert is considered to not have any halachic relations including regarding the laws of mourning, and therefore from the letter of the law is not obligated to mourn his parents. This applies even if his father was Jewish. Nonetheless, certainly he may choose to do so just like any Jew may take upon himself to say Kaddish on behalf of another Jew. However, obviously cannot differ somebody else who was an actual Chiyuv.
Sources: See regarding a convert not mourning his relatives: Michaber and Rama Y.D. 374:5; Shach 374:4; see regarding the laws of precedence: Kiryas Chana 35, brought in Pischeiy Teshuvah 376:7; Beis Hillel 376 that so is implied from Rama ibid and Maharik Shoresh 44; Chasam Sofer 345, brought in Pischeiy Teshuvah 376:7
 See Pesakim Uteshuvos 240:50 and Miluim 9; Encyclopedia Talmudit Erech Kibud Av Vaeim Vol. 26 p. 409
 See Michaber 241:8; Rambam Mamrim 5:9 [regarding father] 10 [regarding mother]; Bava Basra 149a
The reason for the exemption of the mother: If a woman converted when she was already pregnant, then the child born is not liable for hitting or cursing his mother, as the verse states that one is liable for cursing his father and mother and from here we learn as only one who is liable for hitting and cursing his father is liable for hitting and cursing his mother. [Rambam Mamrim 5:10] Now, as for the reason that a Shtuki is nonetheless liable for cursing his mother even though he does not know his father and is not held liable for doing so, this is because if witnesses would come and testify regarding the identity of his father that he would be liable since the potential liability for cursing his father exists he is therefore liable for cursing and hitting his mother and is not included in the above exemption learned from Scripture. [Kesef Mishneh and Radbaz on Rambam ibid]
 Michaber 241:9; Rambam Mamrim 5:11; See Likkutei Sichos Volume 5 p. p. 154 that at the very least they were commanded against shaming their parents and therefore we find that Cham was punished for shaming his father [See Bereishis Raba 36:6; Pirkei Derebbe Eliezer 23; Rashi 9:23] and that is also why Lavan was considered wicked for the fact that he answered prior to his father Besuel [see Rashi Chayeh Sarah 24:50] it is for this reason that is forbidden for a convert to shame his parents as indeed he was commanded in this prior to his conversion. [Likkutei Sichos ibid footnote 38] See there that possibly the source for this prohibition is the fact that we see even Ravens do not shame their parents and we are required to learn from the nature of animals prior to the giving of the Torah [Likkutei Sichos ibid]
 Michaber 241:9
 Rambam Mamrim 5:11; Chinuch Mitzvah 260; Igros Moshe Y.D. 2:130; Kinyan Torah 4:102; Divrei Yatziv Y.D. 127; However, see Shevet Halevi 5 Kuntrus Hamitzvos 24:3; Encyclopedia Talmudit Erech Kibud Av Vaeim Vol. 26 p. 409-410
Other opinions: Some Poskim rule that a convert is exempt from honoring his father and mother. [Tur 241]
 Zichron Yehuda Teshuvos 15
 Implication of Michaber 241:8
 Igros Moshe ibid
 Or Sameiach on Mamarim ibid
 Igros Moshe ibid
 Michaber Y.D. 374:5; Rambam
 Michaber ibid
 Rama ibid; Shach 374:4
Other opinions: Some Poskim rule a convert must mourn the passing of his mother who converted with him. [Mordechai, according to opinion that first day of mourning is Biblical] However, according to our ruling that the first day of mourning is Rabbinical, he is not obligated to mourn his mother’s passing. [Shach ibid]
 Michaber E.H. 4:5 “A Jew who has relations with one of these women, the offspring follows the mother’s identity.”; Rama O.C. 282:3 [regarding getting Aliyah]; Y.D. 159:3 [regarding Ribis]; E.H. 16:2; 44:9; Rambam Hilchos Issurei Biyah 12:7; 15:3-4, 6; Rebbe Yochanon in Yevamos 17a and 23a and 45b based on Devarim 7:3-4; Mishnah Kiddushin 66b, 68b; Ramban on Vayikra 24:10
 Gesher Hachaim 19:3-4
 See Chasam Sofer 326, brought in Pischeiy Teshuvah 345:3, regarding suicide that “although the ruling is that one does not sit Shiva, nevertheless if this will cause the family embarrassment, the Rav may be stringent to tell the family to sit Shiva, as although we are lenient in Aveilus in case of dispute, we are not lenient in the honor of the children of Avraham, Yitzchak and Yaakov.”; See Sefer Toras Hager 12 footnote 98; Pesakim Uteshuvos ibid
 Zekan Aaron 2:87; Yechaveh Daas 6; Nitei Gavriel 40:20; Piskeiy Teshuvos 132:20; See regarding a related issue: Sefer Chassidim 790; Leiv Chaim and Chaim Bayad [Falagi] 33; Darkei Teshuvah 151:29; Beis Shearim Y.D. 229; Pesakim Uteshuvos 240:50
 Sefer Chassidim 790
 Yechaveh Daas 6:60
 Yechaveh Daas ibid