How much sleep should my 7 week old get??

Ma

Its been rough since we brought him home, currently living with my fiance and his parents. He was born 11lbs and seems advanced according to my mother in law, however she also thinks hes ready to be awake more during the day... I'm the stay at home mom and I have issues getting him to stay sleeping after the weekend because she demands to have him and rarely gives him back as well as when she gets home around 4. When I have his routine back to normal during the day (when I'm allowed to set a routine for him) he sleeps happily 2-3 hours at a time during the day and wakes up happy, rested looking and full of smiles. This week he's only been sleeping an hour at a time, waking up yawning, grumpy and the later in the day it gets, the bags start developing under his eyes and gets very prominent. Advice would be very appreciated at this point as I'm at my breaking point