My 2yr old DD is a very good talker. She calls her brother "Baby Joseph" or "Baby Joey." The thing I found adorable was when DD would walk around carrying her baby doll and calling it "my baby Joseph."
DSs name is Luke. My DD called him "uke" for the longest time. Now he's "oompa." The nickname stuck and we all call him that now. She can say the L sound, she just refuses to say Luke. So oompa it is!
DS1 calls DS2 "baby." He seems to understand "brother" (like if I say, "give your brother a kiss") but he doesn't seem to fully understand that his brother's NAME is Jack (and he certainly doesn't say it).
Dd1's name is Audrey and DS was 15 months when she was born. He called her "Ada". Now, both kids are good talkers both over 2 so they can say DD2s name just fine :
Re: Just wondering
DD's name is Emily. DS was a late talker and either called her 'baby', then he said Emmy, now he pronounces her name properly.
DS's name is Austin and she calls him Annie. It's cute