No, contributions into an Irrevocable Trust do not determine the ultimate ownership of the property contributed. The distribution clause in the Trust controls the ultimate disposition.
For example, you have two children, and you intend for them to be equal beneficiaries of your trust after your death. One child has two children and the other child has no children. Structured properly, you could make a gift to your ILIT of up to the annual exclusion for each of the four of them. Say you contributed $56,000 to the trust. However, after your death, each child will receive ½ of the assets of the trust, or in this example (ignoring potential growth) $28,000.