Parent lives on secondary house , rental income?

Hello there,

 

My primary residence in in WA, however, my brother and I co-own a house in Oregon - which is technically still my brother's primary residence, but he's away for his priesthood seminartian,  my parents live on it.  The house is already paid off, but I do pay yearly taxes and home owner insurance under my name. 

 

My question is that, i don't charge my parent rent, but they do pay me for the utilities. The utilities bills is under my name and my dad's name,  the utiliies payment charges directly to my credit card, and my dad paid me back for the utilities bill each month.  Do I have to count the money that my dad pay for the utilities on my taxes as rental income?

 

My thinking is no because there's no rental contract, he's paying me back for the utilities bill that they used living in the house.  The home is still a primary residence for my brother, which he comes from on the weekend.

 

Thank you for your help and answer,

Rose