I do not have a will but my brother is the beneficiary in my retirement accounts

 I live in Philadelphia Pennsylvania.

I am 36, unmarried with children. I own a home with a mortgage and have extensive student loans. No one else signed my student loans except me, so I'm hoping that means that if I die unexpectedly, my family won't inherit it.

I do not have a will but my brother is the beneficiary in my retirement accounts.

My question is about my house. Because I don't have a will, will my family be able to get my house easily if she dies?

I assume the bank will take it to pay off the student loans, but my house is worth about $110,000 more than the remaining mortgage.

(My brother and sister-in-law don't want to deal with a house, so if I die honestly, I'll bet my parents will sell it and give them the money, since my parents made the original down payment, they're obviously very generous.)

Should I write a will? Or is it not worth it to me?

I also don't have an advance medical directive, but I assume my parents would pull the plug if I became brain dead, so I'm not worried. very funny!

Thanks in advance for any advice!