Imagine celebrating Easter with Sirius.
He would be quite a bit weirded out at the thought of running through a park while searching for coloured eggs at first. When he’d notice how excited you were however, he’d finally agree.
It would certainly take some time for him, but after a few hours he would even start getting a bit competitive, refusing to leave the park before he could be sure to have collected the most eggs.
“Sirius, dear, don’t you think we’ve been here long enough?”
“First of all, it was your idea to come here and by Merlin, I will not lose your little egg game aginst some 11-year-olds”