These are from the leaks. Who knows if this was true or not.
I'm leaning towards fake. It was near the end of the messages IIRC, which is when Phil was finally starting to catch on that PPP wasn't actually his friend. Phil has also used the dying parents lie excuse multiple times before. The last time his mom was about to kick the bucket, what actually happened is he got married and got a massive paycheck from his mom after making his 10 year plan.
His parents are old, and we know Linda was a smoker so health problems aren't out of the question...but I don't think they're like, ancient or anything. And I still think with how the goutsphere works, dentractors would know if one of Phil's family members died before Phil did.
I'm starting to lean away from nothingburger and thinking it's a CT trip. But not because anyone is dead, I think his parents either guilted him into it, or dangled money in front of him so he could justify leaving the snortfort.
IMO, it's nothing bad/serious because if it was, Phil wouldn't shut up about it. Even if that means just vague posting. Think about the BK sandwich fiasco, that's usually how Phil acts when he thinks something "bad" has happened in his life. He won't shut up about it and will gladly make himself out to be the worlds biggest victim.
Generally, when Phil is vague about something, it's because he's lying. Like, he'd allude to being unable to pay bills or whatever when he needed to justify begging, never getting into specifics, but when he had to pay his backtaxes, he was always explicit about what he was paying because it was actually a real thing with a solid number attached to it. When Leanna had her panic attack, he was pretty upfront about everything instead of vaguely saying something like "I have a family emergency, I need to go" or even just "I don't know when I'll be back."
I think speculation is fine and all, but I'd give the usual advice of don't get your hopes up for anything too exciting because it'll likely be underwhelming and disappointing.