Stay on visitor visa beyond 6 months with valid I-94

[oooeee]

Hi
My parents are on visitor visa. When they arrived, they were issued i94 for a year. Now, I'm thinking of extending their stay beyond 6 months. 

Do I need to file anything for that? 
Will it create problem the next time they visit?

Can it create problems when they try to renew their visa, which is expiring in 1.5 years?

 

Thanks in advance.

[lovely]

You can extend I-94 while on B2 with a VALID REASON to extend their stay, follow the instructions and complete applications & pay necessary fees asap....there are delays in processing due to Covid so you better be on the safe side if you do intend to extend. Also, you need to secure approved document for future travel, and no, it will not cause any issue while visa renewal as long as you provide a valid proof that its approved by USCIS, be prepared to explain that during the interview and while filing for renewal....even though they know it internally within their system...they might double check just in case.

[oooeee]

Sorry for not making it clear. They got their i94 with a validity of 1 year. If they stay for 8 months, it'll still be within the expiration date of i94   What I'm thinking about is if that's ok? Usually i94 on visitor visa is for 6 months, so will it be problematic if they stay beyond 6 months?