Quoting Masturkate TTC:" My kids both went through this phase but it was a lot longer with my daughter. She barely called him ... [snip!] ... called him dad for like 6 months. She is 2 years and 4 months now and finally stopped calling him Kevin a month or two ago lol."
Did your dude care? Jason doesn't care, haha, like, he doesn't feel like 'less of her dad' cos of it.
He'll be down on the third floor, and she'll go to the stairs and just yell, "JAAY-SIINNN!" cos she hears me do it all the time, haha.