Glad things have levelled out with your ma, even if there are outstanding issues. Also happy to hear Lin can put the hurt to one side, at least in his ways of speaking and relating. You're all doing pretty well, given the outburst! Much love to you all on this one.
Re: scheduled quality time, one thing that's worked for me in the past is to take turns to organise what we'd do for the time we'd set aside. So it becomes a sort of surprise date.
I agree with SNeacail that a whole day could be a bit much to expect, but you could commit to some solid blocked out time for a bonding activity.