Welcome back to the Wefugees Community and thank you for sharing your question.
In August 2018 the authorities re-introduced the general possibilty for people with subsidiary protection in Germany to reunite with their closest family members (underage children with their parents and married couples) here. For a brief overview, you may want to check this website. I would highly recommend you to get support in an experienced migration counselling office as the procedure includes many steps (appointment for visa application at embassy, providing of documents etc.) and paper work. Please let us know if you need support in finding one close to your location.
However, also don't hesitate to get back to us with any further questions.
All the best,