$28M collected: Derek Watt supports brother JJ's efforts to raise money for Hurricane Harvey victims

HOUSTON, Texas -- JJ Watt's fundraising effort for those impacted by Hurricane Harvey was approaching $30 million Wednesday, September 6th, and his brother Derek told TMZ he hopes they'll soon crush that goal as well.

JJ Watt tweeted Wednesday his Houston Flood Relief Fund reached $28 million.

He said his fund received a $5 million donation from Charles Butt, a Texas billionaire who owns a chain of supermarkets.

Meanwhile, TMZ is reporting JJ's brother Derek isn't just praising his brother for raising $27M for Hurricane Harvey victims, he's getting involved, too!

Derek -- a second-year fullback for the Chargers -- was loading up trucks at the "Chargers Food & Supply Drive to Aid Hurricane Harvey Relief Efforts" in Los Angeles on Wednesday ... along with several teammates.

Watt said he's been texting with his family about J.J.'s fundraising -- and thinking of other ways they can help out.

In video shared by TMZ, Derek says he's "extremely proud" and vows to help push the magic number to over $30 million.