A family consultant - the expert witnesses used to assess family dynamics for court proceedings - would give negative feedback on a parent who gives kids a choice about whether or not they see the other parent. Kids below the age of about 12 shouldn't be given a choice because they're not capable of deciding for themselves what's in their best interests, and it's a parent's duty to actively encourage the kids to spend time with the other parent.
You'll need to organise a family dispute resolution conference with the other party to try and reach agreement about care arrangements for the kids. This is a mandatory pre-procedure step - if you can't reach agreement, you'll be given a s60i certificate enabling you to file an initiating application with the court.
Remember, previous orders have effect until the kids turn 18, and different rules may apply dependent on the nature of the orders already in place. Are they parenting orders made after a trial at court; consent orders made by agreement of both parties and formalised by the court; or a parenting plan?