Grandson's Dad disapproves

They argued after she became pregnant and she moved in with us. I went to birth classes and was there in room for delivery-my most wonderful experience. The Dad was there too but then since he did not ask her to move in with him, she came back with us for 2 and a half months. My grandson and I bonded and I love him very much. She bought a house by herself 3 miles from us so we see this little boy very often and he adores us. He is now 2 and a half. The Dad rented out his house and moved in with our daughter a year ago He does not pay my daughter much at all for living there-has a good job. He does do the snow blowing and mowing and buy some groceries.They just went to Vegas for 6 days and we kept our grandson. When they returned at 9 am he had just woke up and was clingy and wanted a bagel but Dad said NO- he should wait till they got home. Grandson cried and wanted me to comfort him. He then wanted me to carry him to their car. Dad was very annoyed and showed it, but I did carry him as he always wants only me to put him in the car .

The Dad was very nice to me before they went to Vegas and is nice when they want to go on a weekend motorcycle trip because we are the babysitters, but he says I "baby" his son and is sometimes very unkind and rude to me. I am a very loving person and the little guy often wants me to pick him up and hold him and cuddle or read to him and I always do. He is a sweet child and good but but like any 2 year old can be difficult. I think his Dad expects too much and wants him to always be good.. I feel very uncom fortable around this man when my grandson is there so I try to ask my daughter to pick up her son when he is staying with us rather than taking him home. She is fine with the close relationship we have with our grandson but will never say anything to his father about the way he behaves to me and my husband. She also does not ask him to contribute more financially although I know she has some resentment about that. We do nice things for them often.  I truly think my Grandson's Dad is jealous of the close relationship we share with the little grandson. He does love his Daddy and his Dad takes him to the store with him and other places but he is a gruff person and does not actually play with him or rarely reads to him. I play with my grandson and when I am with him that is what we do. Does anyone have any advice for me or any comments. Thank you