Q. Does one have to stand for an elderly person if he is mochel, forgives or does not want you to stand for him?
A. Teshuvos Radvaz (8:167) maintains that even when the elderly forgoes his honor, one should still respect him by rising slightly. Horav Y.S Elyashiv zt”l, however, rules that this is unnecessary. (Mevakshei Torah, v. 4, p. 249).
Horav Shlomo Miller’s Shlit’a opinion is similar.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a