My children are all older than DB's DS so when DN came along I offered DB and SIL the pick of all my baby things. They took loads high chair, travel cot, all DS's baby clothes - great, both families happy, I have more space they have lots of baby essentials they don't have to go out and buy. 
Over the last couple of years as my DS has been growing out of clothes and toys I have always put the good stuff to one side and let SIL take any of it she wants and she regularly does which again is great!
A couple of weeks ago my washing line fell down and my dad offered to cement it in while we were on holiday (kids not around, allow time for the cement to dry without children interfering) which he did and I was extremely grateful. When I got home he said that as he only needed a little bit of cement rather than buy a bag DB had given him a little bit and told my dad to tell me
"don't worry about paying me for it next time you go shopping just by DN a little something"
I was a bit [shocked] tbh but AIBU?