I have seen some homes where the children refer to the parent in third person as a sign of respect (Would Abba like to...). I'm curious to know if this practice is brought down in any sefer and if in today's age where no one speaks like this to anybody, it is still considered a praiseworthy way of addressing a parent.
Shulchan Aruch Yoreh Deah Siman 240:2 says “it is forbidden to call a parent or refer to them by their name; rather they need to be referred to as “My father [my teacher]”.
This post shows that the use of the third person was well-known in the past.
But for today, Rabbi Simcha Weinberg in his blog says “My father zt”l often explained that each generation demands increased forgiveness of Kibbud than the previous generation. He insisted that I do not allow my children to speak to me in third person.” (IMHO, he means that the parents cannot require the same Kibbud as the previous generation.)
Harav Avraham Rosenthal in Kibbud u’Mora Av ve’Eim: Honoring and Fearing One’s Parents writes, “When speaking to one’s parents, he is allowed to address them in second person, i.e., you, even though he would not speak this way to a talmid chocham Aruch HaShulchan 242:38. However, in those communities where the custom is to speak to a parent in third person, it is considered disrespectful to address them in second person (Sefer Mora Horim u’Chvodam 3:20).”
In my experience the use of the third person is certainly not unknown today, even to grandparents.