Nowadays, individuals spend significant time on online social networks and microblogging websites, consuming news and expressing their opinions and viewpoints on various topics. It is an excellent source of data for various data mining applications, such as sentiment analysis. Mining this type of data presents several challenges, including the posts' short length and informal language. On the other hand, microblog posts contain a high degree of interdependence, which can help to improve sentiment classification based on text. This data can be represented as a graph, with nodes representing posts and edges representing the various relationships between them. By using recently developed deep learning models for graph structures, this approach enables efficient sentiment analysis of microblog posts. This paper utilizes graphs to represent microblog posts and their various relationships, such as user, friendship, hashtag, sentimental similarity, textual similarity, and common friends. It then employs graph neural networks to perform context-aware sentiment analysis. To make use of the knowledge contained in multiple graphs, we propose a stacking model that simultaneously employs multiple graph types. The findings demonstrate the relevance of sociological theories to the analysis of social media. Experimental results on HCR (a real-world Twitter sentiment analysis dataset), indicate that the proposed approach outperforms baselines and state-of-the-art models.