He won't do it.
Mike Pence won't invoke Section 4 of the 25th Amendment to the Constitution and remove Trump from office. He doesn't want to make Trump, who can appeal such an invocation, angrier than he already is. And that would be reasonable argument if Trump weren't so angry now, having lost business deals and his Twitter account, that there's no way he could be any angrier.
If Pence doesn't invoke 25-4 per the U.S House's request, the House will have to impeach Trump tomorrow.
And then he'll really be mad.
Section 4 is the only section of the 25th Amendment that has never been invoked before.