You can open a family plan, which allows you to save for multiple beneficiaries under the same RESP, if they are all siblings by blood or adoption.
A family plan will allow you to allocate your contributions to any beneficiary you wish, and the savings, grants* and income you accrue can be shared among the beneficiaries.
Each child is entitled to a $50,000 lifetime maximum contribution limit within a family plan. This means that if you have two children within a family plan, you can contribute a maximum of $100,000 without incurring penalties.
*to a maximum of $7,200 Canada Education Savings Grant per beneficiary