Is there a stairgate a 4-year old can open

[Stuntnun]

My 6-month old DS2 has just got to the dangerous stage and is ready to roll down the stairs at any unattended moment. So obviously I need a stairgate. Problem is DS1 has just turned 4 years so I really need a stairgate that he can open. (I have vague memories of having to climb over my little brother's stairgate when I was 6-years old.)
Has anyone found a stairgate that is easy to open? My stairgates for DS1 involved pressing a button and lifting the gate and I don't think DS1 could manage that.
Just to make it even more complicated, my Dad has Parkinson's and it's hard for him to lift his feet high off the ground. So a stairgate with no bar at the bottom would be brilliant too.
Please help, at the moment it looks like at least one of them is going to end up falling down the stairs.

We have the sort that fix to the wall, mothercare I think. DS1 could work them at that age.

DS could open one that was just a squeezy handle type at 2.

the one pictured first here

Thanks, that squeeze handle does look easier.

Go somewhere where they have them on display and he can try it out before you buy one.

Toys r us, mothercare?

we have the ones you can describe and dd1 (3.10) can open them. we also secure them below the step, not on the step so there's no risk of tripping over - ideal for your dad. think our make is lindam