Suggestions for Midlands(?) day out

[granolaelephant]

First time posting so please bear with me!
I'm looking for recommendations for a meeting place/ day out venue.
I live in Oxfordshire and my parents are in Manchester. My dad had a stroke in December and is now a wheelchair user as his mobility is very limited; he also has various other health problems meaning he rarely (if ever) gets out of the house.
I have a four-month-old who my parents have only seen once, and we are trying to find a midway location to meet up so they can see their grandchild more regularly. It would have to be within 1 1/2-2 hours of Manchester, but also ideally not much more than 2 hours from Oxford as I don't want to spend all day driving with a baby. Everywhere I've looked seems great until I read TripAdvisor reviews and find it's actually unsuitable for a wheelchair, despite claiming accessibility! It needs to be somewhere with A* disabled access as the wheelchair isn't the most robust (think of the small wheeled type) and my parents aren't very confident with it, plus my dad gets very stressed by any hiccups, however minor.
I was thinking a garden/ National Trust property/ nice pub but anything that meets the geographical and access requirements would do!

Trentham gardens might suit- the shopping village and garden centre are easy walking, a lot of gravel in the gardens.

Or here? https://www.staffs-wildlife.org.uk/explore/our-visitor-centres/wolseley-centre

Trentham Gardens might fit the bill

I was going to suggest this place- it's pretty flat, but the info on accessibility on their website is sparse. Worth a call. It's stunning in autumn.
https://www.thenma.org.uk/

I’m sorry to hear about your dad.
Walsall Arboretum is brilliant. All smooth tarmac paths. It’s best if you enter from the main entrance, otherwise the path from Buchanan Road is a bit steep. The cafe and visitor centre have disabled access too.
Aston Hall is pretty good. It has ramp access to the main buildings and tarmac paths around the site. The lower floor of the house is very accessible with ramps between rooms where necessary. The upper two floors are not accessible but there is a virtual tour of those floors available for people who can’t get up there, which is a lovely touch. Tbh the best bits of the house are on the ground floor anyway. The Stables Cafe is all on level access.

Thanks all for the suggestions - think we'll try Trentham Gardens this time and bear the others in mind for future visits.

Another Trentham Gardens vote here. The gardens are beautiful and accessible and lovely for your daughter to play in too when she’s older, your dad should be able to see her play from the path too. Lovely eateries too.

I was just going to say Trentham Gardens too!