They are separate of course because they are two different coins. Both are traded independently from each other. Moreover, the demands of Bitcoin and Ethereum are moving separately. So you cannot expect that the two will move at exactly the same time and with exactly the same pace.

You do not just count the number of days of their uptrend or downtrend movements. These movements show us something of course but not everything. Not a big deal in other words. Bitcoin has actually recovered more than Ethereum. Ethereum has more lost value as compared to Bitcoin.