stand up with
Verb
Meaning
(transitive, idiomatic) To publicly support (someone).
(transitive, idiomatic) In a wedding ceremony, to serve as best man or as maid of honor or as an official witness for (someone).
(transitive, idiomatic, archaic) To begin to dance with (someone); to dance with (someone).
Source: en.wiktionary.orgExamples
“Industry is starting to stand up with a lot of the commercial satellites,” said Maj. Janelle Jenniges, Air Force Space Weather Integration chief.
"I'm going to go out there and stand up with him because that's what everyone wants to see.