Myself and my siblings gradually left home, and lived quite far away in some cases. Over the years my Dad started a habit of ringing us all on a Sunday morning, just "Keeping in Touch" . That way he got a weekly update and we expected his call.
Looking back, it was lazy of us as adult children, we let him do it mostly.
Be proactive to improve things for the future. How about setting up a family whats app group? It's easy to do and great to keep a spread out family connected. We have one group with me, my siblings, all the adult children and a cousin or two. Any of us can just post a picture, or message, and they can read it when they choose. Better than a phone call if they are often busy.
You could also post on there, ask if convenient to pop round for an hour, suggest a day. Don't let this drag on any longer.
Would you like to see Cinderella performed by a male dancer?
No win no fee are they worth going down this rout if decided to take further