If the question is: "IS there a way", the answer is yes.
If the question is: "is it likely", there answer is maybe.
There is monitoring software available that will sniff and record all network traffic through the access point/router that your parents can install on a PC or cell phone.
Absent that, your access point itself may record internet history over a period of time that can be accessed by logging into the access point. Not all of them do this though, and many of the ones that do store IP addresses instead of URLs, so your parents would have to put some effort into the project to get any useful information out of it.
ISP's themselves have a wide range of policies on if/how they track web history, and whether they'll release it upon request if they do. In most circumstances, though...this isn't a realistic option.