The law protects you against contract termination during you parenting leave. This means that when you parental leave is over you are indeed entitled to get your job back. This protection ends 3 month after the end of your parental leave. But the protection doesn’t apply if you are being lay-out for a serious cause.
More information
http://www.onem.be/fr/documentation/feuille-info/t19#h2_22
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