Maria ascribes her aggressive behaviour

[Bassim]

I am wondering if my sentences are grammatically correct. I believe that my second sentence does not sound natural.

Maria ascribes her aggressive behaviour to her difficult childhood. She witnessed her parents arguing and fighting almost daily, and she could not remember spending one holiday without their parents' quarrel.

 

[GoesStation]

Here are two problems to rectify:

Their requires a plural antecedent. Use a different pronoun.

Her parents' quarrel isn't a thing that would follow the family around on vacation. Use a gerund.

 

[Bassim]

Would this version be better?

She witnessed her parents arguing and fighting almost daily, and she could not remember spending one holiday without them quarrelling.

 

[GoesStation]

Would this version be better?

She witnessed her parents arguing and fighting almost daily, and she could not remember spending one holiday without them quarrelling.

Yes, much better. We spell that last word quarreling in American English but I think you've got it right for the British variety.