Sayyed Mohammad Al-Musawi, Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to... Answered 3 years ago

Muslim is not allowed to attend or take part in any non Muslim religious ceremony.

The child mentioned in your question is a Muslim because of his Muslim father. Islam says that any child who is born from Muslim father or Muslim mother, is a Muslim.

الولد يتبع أشرف الأبوين 

There is no question of baptism ceremony for a Muslim child.