Birmingham advice

Cannon Hill Park has a couple of typical play areas and a mini golf course, but the big draw for small children is the Fun Park which has a few rides, remote control boats, inflatable slide etc... You can get a Fun Pass which also gives access to the pedalos on the lake, or you can pay separately. At one side of the park there's the wildlife conservation centre which has a good collection of interesting animals including a lynx, red panda, monkeys, lemurs, otters, wallabies, lizards etc... There are a couple of nice cafes in the park too.
Birmingham Thinktank is an amazing science museum that always has a lot to do for all ages.
Birmingham had all of the family-friendly chain restaurants like Bella Italia and Pizza Express, but if you're after something a little different, Nosh and Quaff is good and eating with your fingers is totally acceptable! Bar Estillo is a cheerful tapas restaurant with a kids menu including spicy meatballs, paella and nachos.

I agree with the above - cannon hill is lovely park and my kids enjoy the golf and the fun park when we go there. The cafe there is also good.
Which area of Birmingham does your friend live in?