Does the subject of this sentence make sense, even when split by the clarification?

Question

I'm trying to be as terse as possible in expressing a few points, so I've ended up with the following sentence:

During the summer, my sister and brother, younger by five years and older by two, respectively, and I lived with our mother.

Is this grammatical and does it sound strange to read? Is there a better way to write it?

Answer 1

Your sentence can be even terser: During the summer, my sister (5 years younger), brother (2 years older), and I lived with our mother. The original is a bit clunky and awkward because of the way the ages of your siblings are inserted, especially that "respectively" bit, which is sometimes okay for technical writing if it makes understanding the sentence easier for the reader.

Your sentence is perfectly grammatical, but it sounds a bit strange because the style isn't formal or informal, just awkward.