how to deal with inconsiderate roommates that is a family with a baby?

Recently I moved to a new place. when I made the offer, it was under the impression that I will have 2 other single female housemates. Before I moved in, it was also agreed upon between me and other housemates that we will use the living room to work remotely whenever needed. We all WFH 2-3 days a week only (not all the time).

Then, the day I moved in, the main tenant (one of the girls) told me that the other girl will be moving out in 2 weeks, and a family with a 10 month old baby is moving in. I was shocked, as this was not what I had agreed to when agreeing to rent the place but as the main tenant was overseas for 2 weeks on holiday, I decided to wait until she's back to discuss this.

(Context: The main tenant deals with who moves in rather than the landlord, who is living overseas. The lease is under the main tenant's name.)

The family are terribly inconsiderate housemates so far. They like to blast their phones at the loudest volume and the flat has terrible sound proofing so I can hear it even in their room. They had a lot of stuff, especially baby stuff, and they reorganized the kitchen to accomodate their stuff. They had also overtaken the living room, moving a baby mat and cot into the living room. It is noisy and distracting and I can't concentrate when I WFH. They are messy around the kitchen, rarely cleaning up properly and I have to remind them to do several things or clean-up after them. I had to remind them to take down their laundry so I can do mine, when their laundry has been hanging for 3 days. Both parents are also working remotely/freelance full time so they are mostly home.

How should I approach this situation? They are supposedly staying for 2 months for now, but might be extending if they find full-time jobs. I can tolerate this for 2 months but I will go crazy if I live like this any longer. I just moved into the place, and I rather not move again at least for a year.