My Ex has been going shopping with our D5 for a few years now for my birthday, fathers day and the holidays. This year, she got me some twizzlers and a few nice ornaments (one with a cute santa and a Dad sign).
We shopped for her and she picked out a few nice gifts for her mother as well.
Aside from a few disagreements, we have actually been moving closer to effective co-parenting. We have been parallel parenting for a few years now, which has worked out quite well. As D5 gets older, I think we are learning how to communicate more effectively.