Native Swahili speaker and pretty sure mfuko is also a pocket. This was marked wrong though. Perhaps differences in Kenyan and Tanzanian Swahili?
Mfuko is definitely a pocket, but it can also be a small bag. You should mark it, though so that they will accept both answers.
A bag with a child does not make sense - it could be perhaps "mtoto na mfuko" "a child with a bag" - that would make sense.
Mambo rafiki! It is also possible to use "the" with the nouns in Swahili, because Swahili does not use articles.
You can translate this with many possibilities, for example:
Bag and child/kid/baby.
A bag and the child/kid/baby.
The bag and a child/kid/baby.
A bag and a child/kid/baby.
The bag and the child/kid/baby.
Note: If you see something wrong with these translations then you should report them. ;)