As a mother of a four-year-old boy, I think I might enjoy Charlie and Lola just a little bit too much - both my son and I think these two characters are absolutely hilarious and endlessly charming. Their little voices and mixed-up grammar just add to this, although I did have some doubts initially as to their use of the English language. Then I realised that all children mix up their grammar, and put words together in "odd" ways, and listening to Charlie and Lola couldn't possibly be any more detrimental to my son's linguistic development than his attending preschool with a bunch of likewise grammatically-challenged children.
Charlie and Lola is a wonderfully witty series, which my son and I thoroughly enjoy. Highly recommended viewing, I would say, for its quirky graphics, charming depiction of sibling relationships, and child-centred perspective.