Your baby's 14th week
Your little one will enjoy experimenting with his voice. He's probably developing quite the "vocabulary" lately. He'll say vowel sounds like "ooh" and "aah" and has learned that he can change the sound at will by simply changing he shape of his mouth. In addition to these vowel sounds he'll continue gurgling and making throaty sounds. He may also enjoy blowing bubbles.
Watch his legs continue to strengthen as he stands with your support, bearing his own weight. Depending on his strength he may even be able to sit (propped up) very soon though most babies are in their sixth month before they're able to sit without assistance.
His mind is hard at work as well. He's starting to develop mental images of the things that will happen when he "asks" for assistance. He's able to envision certain cause and effect relationships. (Chewing on his fist = nursing.)