I discovered Aleks with the Lincoln Log instructions out, having followed them and built most of this house in the dining room. Bastian came to give it a look-over. He gently places the roofs.
Then Bastian tries to help by adding multiple chimneys.
Aleks rejects Bastian's participation, but poses with his house. He had shown very little interest in building with the logs at all in the past, and generally hadn't been able to figure out the pattern to make whole buildings. Clearly, that is no longer a problem!