That is certainly behavior I wouldn't want to see. I don't know if it's aggression as much as prey drive, imagine when the baby starts crawling? Has this dog ever been around kids ? I would also consult a trainer ASAP.
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD