Recently, a client who was blending families asked about how to get through the complexities. My main answer was a single word, "Flexibility!" With the unique history of step siblings, parenting styles, and age/stage variations, the one thing you can count on is group dynamics that are ever-changing. Use this rhyme as a therapeutic guide for starters:
Whether it's hers and his, or his, hers and ours,
To blend a step family takes nurturing powers.
There are infinite types of special family blends,
And they all grow best with a love that never ends.
Each member is unique, with needs ever changing;
You must be on your toes and always rearranging.
Let your inner wisdom always be your guide,
And you will find joy on this wonderful ride!
The other primary ingredient is open, honest, and respectful communication. It is easy to get lazy about communication when in a newly blended family. It's unfamiliar (at least some of the new members are), and confusing to know what to say, or not say. Sometimes people default to saying nothing and avoiding communication due to these uncertainties. The best cure for that is to ask neutral questions that come from genuine caring and curiosity. The newer the union, the better it is to stay away from known defensive topics at first. Stay with getting to know you conversations.
An example of this type of question would be, "I'm realizing there's so much we don't know about each other. Can you help me a little bit? For example, could you let me know what some of your favorite foods are? Then share some of yours in response. What type of meal times do you prefer? We can try to make sure we do that as much as possible. Do you have any questions or suggestions for me?"
By starting with basics and showing you want to be respectful of creating comfort, you have a better chance of keeping open communication as the relationships mature. Eventually, sharing that as your high priority helps make the family unite with common, albeit newly blended values.
Finally, don't get dejected if it takes a while. The discomfort isn't usually due to huge problems, it's due to long established habits that are now rearranging. Don't expect instant love and harmony. Instead, go for admitting it's all new to all of you, and you'll be doing your best to get comfortable as the new family evolves into its special groove.