The movie has a brother and sister , the brother is wearing a grey jacket or wind breaker and the older sister is wearing a yellow one , they find there grandpa’s amulet or something and it transports them to a different place and are trying to get back home and are traveling with a muppet creature but not the actual muppets and I believe they have to wake up a giant that’s sleeping in order to get back home . This movie i remember seeing back in the early 90s , it was in color but it felt like a movie with sesame street quality if that makes sense. Please if you can find this movie and let me know it would mean the world to me !