my dd just turned 2 and is very smart and well balanced, but im worried about her speech. she has a minor lisp which is fine, but she only says single words, and is not forming sentences or making demands. when she want something she just cries and whinges and i hardly ever know what she wants. is this normal, and will her speech improve without therapy?? anything i tell her to do she understands like put the wrapper in the bin, everything really, and if i tell her to say something she does it, she chatters in gibberish for ages, but not proper words. should i take her to see someone about it??