Which small furry animal shall we get?

[Freddiecat]

DD would love a small furry animal for her 9th birthday. We already have 3 elderly cats and a youngish dog but the creature would be kept ideally in her bedroom which we can keep the other animals out of. Her bedroom isn't massive but there is a chest of drawers the cage can be kept on.

We've been to Pets at Home and had a look and the choices are:
Hamster
First choice but nocturnal. They say playful in the evenings but will this be from 4pm onwards? Or are they not likely to wake up until 10pm?
Dwarf Hamster
As above really.
Gerbil
Seem livelier during the day but do they need a really deep cage for burrowing?
Degu
Very cute in the shop. Concerned they need a bigger cage and also the whole thing seems more expensive esp. as we'd have to get at least 2.
Guinea Pig
She likes these but it seems like a whole lot more work than the others. We have a garden with grass we are not precious about so could put a run outside in the summer. Really given our wet summers I wanted something indoor so she can interact with it/them daily.

Advice needed please!

Posy, our cat's favourite place is lying by the fishtank (full of fish rather than furries) and prodding the sides occasionally to alarm the occupants. If it was full of squeaky prey I don't think he'd be able to resist.

I don't really think it would be fair on any small furry creature to be kept in a house in which they can constantly smell predators. However, if you do go on to get one, rats are crepuscular, so are awake from midday/pm to late evening, and are ideal to that extent. They DO need to be kept in pairs/groups, however, as they do not live alone naturally, and need company most hours of the day to be truly happy.
Rats are, however, considerably more intelligent than hamsters et al, which may be great if your child is a keen, interested and committed pet-owner, but could equally mean greater suffering if the creature is kept in its cage 20 hours of the day/ hardly handled or entertained. A hamster might bear that with greater equanimity, I think. rats are estimated to have the intelligence of the average dog, to give you some idea - and yes they can be rained to carry out a number of tasks, and enjoy doing so. hamsters and gerbils, form my experience, are often more of the eat/sleep/shit/die order of existence, cute though they are.

Trained

My DD approached the "I want a Pet" subject when she was 9yo. She originally wanted a hamster because her friends had them, but I don't like them (I know , it's not all about what I want but I know I'd be responsible for them)

If she'd had a hamster I'd have let her keep it upstairs in her room but had another play area downstairs so it could be a family pet as well as her pet.

But I made her see sense explained the joy that is Guinea-Pigs and we have the boys.

They are messy, greedy, take over your house (not just the space but their hay, little droppings and bits of veg turn up everywhere)

Our guineas have their own bedroom for winter nights (it's the small boxroom/ storeroom but they don't mind, it's quiet and not too warm)

If I didn't have the guineas I'd have gone for female rats personally. But GPs are nice and dim IME

GPigs safest with the cats.
I vote fancy mice (yeah I know not on your list). Low maintenance, don't live too long, high cuteness factor, don't bite, cheap when you find a supplier, smallest cage.

Hamsters ideally want to burrow, too, btw, should have deep bedding.

We are just pondering this.

We have had guineas, outdoors because our house isn't big enough for a suitably sized indoor cage. This caused some problems getting dcs to go out come rain or shine to clean out and feed and handle. They were lovely but I found them a bit 'boring'. They just arent as playful as the smaller furries. They are very good if you want something to sit and cuddle and groom.

Our next pet is going to be an indoor small animal. I have asked advice at 3 different pet shops and this is the 'ranking' with which they recommended for my circumstances (indoor pet. 3 children aged 7-9). 2 pet shops were pets at home, one of which just pressured us to buy the rabbit dd3 fell in love with. The advice at the other 2 was very similar and I felt much more comfortable that it was a discussion. A 2 way discussion.

First choice rats if we have the space (I'm not sure we do)
Gerbils
Hamster
Dwarf hamster.

Gerbils are more alert from tea time (apparently). I think we will be going for the gerbils.