Downsizing

Why is when either David or I are gone, Easton is awesome. Not very whiny or fussy and listens to what you say yada yada yada. But the min. one of us comes back, he becomes the whiny, fussy, no minding kid. I don't get it. When I am away from him I will come home and always asked David, or usually David will tell me he was really good. All he kept saying was Momma Bye Bye, Momma Bye Bye. If they go to dinner he is awesome too. When David leaves it is the same for me. We can't figure it out.
For instant, David wanted to go fishing with his buddies, but it was an overnight trip, no biggie. So David left Sunday afternoon. Easton and I ran some errands and then we came home and play and then he went to bed. Monday morning, he woke up and I fixed him breakfast and he sat at the island and ate his oatmeal. I told him if he needed me to just holler and I proceeded to do my hair and makeup. When he was finished he yelled Momma, I dun. I put him down and he played with the dog and I finished getting ready. Got him dressed no biggie.
Tuesday I told David what I did in the morning...umm Easton sat there a whole 2 mins and then wanted David. then he whine about this and that. Then when I told him it was time to get dressed he ran away from me and laughed...I don't get it.
I think David and I need to downsize lol. (no we aren't getting a divorce or one of us isn't moving out) but it just has me confused.