internationally adopting 'older children' AND sibling group?

My husband and I currently have no children and we are working with an adoption agency. We are fairly certain that we wish to internationally adopt a child who is a toddler or slightly older. Would anyone be willing to share there experience/knowledge with regard to post-placement of older children? ALSO, we are seriously considering the idea of adopting more than one child at a time--that is, a sibling group. **However, the likelihood of being referred a sibling group of three or more children is much greater than a sibling groups of two.** But, we have some concerns about taking on an adoptive family of that size all at once. I would greatly appreciate any and all feedback. Thanks!