From the Ravs Desk: Latest articles and Q&A [Tuesday 12th Tamuz 5785]

A change of location may be considered an interruption that requires the recitation of a new blessing before continuing to eat or drink. This requirement depends on several factors, including the type of food, the new location, visibility of the original area, intent, group dynamics, and the status of the food being consumed.

Factors Influencing Blessing Repetition:

Several factors influence the necessity of repeating a blessing after changing locations:

• After Blessing Type: The requirement to repeat a blessing is only applicable to foods that have the after blessing of Borei Nefashos, or if one ate less than a Kezayis of a Meiyn Gimel food. However, not if one ate a Kezayis of a Meiyn Gimel food, or even less than a Kezayi of Hamotzi bread if he returns back to his original location.
• New Location and Intent: Even by Bore Nefashos foods, changing from one room to another within a building only requires a new blessing if there was no prior intent to change. However, moving from inside to outside necessitates repeating the blessing even with prior intent.
• Visibility: Even by Borei Nefashos foods, if one can see their original eating area from the new location, they do not need to repeat the blessing.
• Group Dynamics: Even by Borei Nefashos foods, if someone is eating with a group and some members remain in the original location, the blessing does not need to be repeated upon returning to that area. However, if one wishes to continue eating in a new location, a new blessing is required.
• Kevius: Even by Borei Nefashos foods, if one someone establishes themselves to eat or drink a Kevius food (like bread, wine, beer, or coffee) and leaves the area with intent to return, then there is no need to repeat the blessing if they briefly leave and return.

Sources: https://shulchanaruchharav.com/halacha/chapter-20-shinuiy-makom-the-laws-of-blessing-repetition-due-to-change-of-location/ 

Yes. This is correct.

See here for the two opinions on the subject: Admur in Seder 8:6; Luach 2:7; 472:20; 612:15

Yes it does, but only from the aspect of having offspring. Thus, there is no technical Halachic restriction against the couple being ten years apart for example, other than the above aspect of whether or not he/she can have children. Notwithstanding, however, it is not recommended for there to be to much of an age difference despite the Halachic allowance. All in all, Halacha does not dictate prohibition in these matters.

See Michaber and Rama E.H. 2:9